In the field of vehicle mounted travel control systems, many type of navigation systems have been proposed in the past. FIG. 13 is a block diagram showing a conventional vehicle mounted travel controlling system.
Referring to FIG. 13, a central control section 101 synthetically processes information from control sections such as an engine control section 102 for controlling an engine of a vehicle and a transmission control section 103 for controlling a transmission. In this context, "synthetically" means that the control is comprehensive, that is, that the central control section 101 controls virtually all control sections. Also, a navigation system control section 104 controls navigation of the vehicle and a storage section 105 stores map information. A course decision section 106 processes information about a destination of the vehicle and a designated course to determine the future course of the vehicle, a position detection section 107 measures the present position of the vehicle using signals from a sensor or an artificial satellite, a display section 108 displays the map information, the present position of the vehicle and the future course of the vehicle, and a voice message notification section 109 provides voice messages. Generally, an automobile includes, as shown in FIG. 13, the engine control section 102 for processing information from various sensors and the transmission control section 103, and controls the engine, transmission, suspension, steering system, air conditioning system and lighting device, etc., under the control of the control sections.
The conventional navigation system can designate a starting point, a destination of the vehicle and a designated course based on the results of processing by the course decision section 106 and the position detection section 107. A scheduled course of the vehicle is calculated by the course decision section 106 in combination of the map information previously stored in the storage section, and as a consequence, the present position of the vehicle and a direction of travel at an intersection and the like are displayed on the display section 108 or provided by voice with the voice message notification section 109, whereby the vehicle can be guided.
In the above prior art, a navigation system is described which guides the vehicle by displaying or providing an audible indication of the present position of the vehicle and the direction of travel at an intersection and the like. However, other conventional navigation systems include those which can calculate a distance and a required time between the present position of the vehicle and an intersection and the like where the direction is changed, and can inform the driver of the change by voice or by a visual display. Prior art systems also include those which can obtain weather information and information about vacant parking lots from radio transmissions sent by a radio station and the like, and can provide this information to the driver, again either visually with a display or audibly with a voice-based system.
As prior art in which the sensors and control device of the aforementioned vehicle are used, for example, a traffic jam travel detecting apparatus is disclosed in Japanese Unexamined Patent Publication No. 63-172397. The conventional traffic jam travel detecting apparatus calculates outputs of vehicle speed sensors, judges that a traffic jam exists when the vehicle is traveling at or less than a predetermined speed based on the calculation results of the calculated output of the vehicle sensors, and controls a vehicle height adjusting device, suspension, automatic transmission, and engine based on the result thereof.
In addition, other conventional traffic jam detecting apparatuses, which detect a traffic jam by using the outputs of the vehicle speed sensors, are disclosed in Japanese Unexamined Patent Publication Nos. 59-200845, 59-200846, and 59-200847.
Further, an apparatus for controlling the shifting of an automatic transmission based upon the number of revolutions of the engine and vehicle speed, an apparatus for controlling a vehicle suspension from a rotation angle of the steering wheel and a vehicle speed, an apparatus for controlling a gear change-up timing or gear change-down timing with the back-and-forth inclination of a traveling vehicle, an apparatus for controlling a lighting device in accordance with surrounding brightness, and an apparatus for controlling a vehicle height in accordance with a vehicle speed are all known.
A system in which a vehicle is controlled on the basis of information from a navigation system is also known. For example, a vehicle air conditioning apparatus is disclosed in Japanese Unexamined Patent Publication No. 4-201712, and a hybrid-type vehicle is disclosed in Japanese Unexamined Patent Publication No. 6-187595.
The former vehicle air conditioning apparatus controls an air conditioning device of the vehicle by the map information of the navigation system and travel information in such a manner that an air conditioner is automatically switched from external air inlet to internal air circulation when going into a tunnel, and controls an air conditioning device of the vehicle in a traffic jam by judging the traffic jam environment with a distance traveled per hour. The latter hybrid-type vehicle increases accuracy of information for guiding the vehicle by adding information about the road on which the vehicle is traveling to the map information of the navigation system, and switches a drive force (specifically, an engine and a motor) responsive to the travel position by adapting the vehicle to the condition of different environment even at the same point, such as a multilevel intersection.
Since the conventional central control section and navigation system of the vehicle are separately and individually constructed as described above without combination, they cannot control the vehicle by mutually using the information from the sensors and the navigation system mounted on the vehicle.
In addition, although they can judge the position of the road along which the vehicle passes immediately after a present position (imaginary course), they have no means for knowing the condition of the imaginary course. Therefore, since various control operations are performed after obtaining the present information from the sensors and navigation system mounted on the vehicle, the control of the vehicle may be delayed, or the vehicle may be erroneously controlled.
Further, conventional navigation systems can virtually move the vehicle on a map when calculating the scheduled course. However, this is performed by using predetermined data such as a vehicle speed, and conventional navigation systems can not use the actual vehicle speed of the traveling vehicle, and further, can not predict the intended travel position after the passage of a predetermined time with reference to the present position.